Thank you ET and Yendor.
You guys nailed it.
I don't think I should be asking anymore questions about this.

But, please spare with me to post something from 'cyber university'.

I just came across this web page yesterday, which explains the workings of the charging system, but also advises about something I'm bit worried about.

http://www.chargerr.com/Alternators/ALT.HTM

SENSE
The SENSE line is a positive input to the alternator, and is meant to be feedback giving reference information on the load of electronics on your car. So its supposed to be hooked up the most electrically distant part of your car to let the alternator know if it should be upping the current to compensate. If its hooked up close to the BATT wire, which will be virtually the same voltage, then the alternator doesnt think it has to work that hard, and just does enough to keep the voltage steady at 13.8V. Not a bad thing if other systems in your car, like amplifiers, or fuel pumps dont mind getting a little shy of 13.8V.
The above is confusing because of the below thread and the ideas we discussed there, and of course in this thread as well.

http://www.patrol4x4.com/forum/auto-...-cable-319529/